Membership questions? Log in issues? Email info@brewersassociation.org

Author Topic: Plastic/Phenolic off flavor after bottle carbonation  (Read 4112 times)

Offline Guilherme_HCV

  • 1st Kit
  • *
  • Posts: 9
Plastic/Phenolic off flavor after bottle carbonation
« on: May 05, 2016, 08:41:56 am »
Hi experts,

On my last two batches i noticed that after the bottling (tastes and aromas were very fine before it) when 7 to 10 days was passed i noticed a fine carbonation, but noticed a plastic aftertaste and a little bit at the aroma too.
I believe it is not chlorophenolic,but something like styrene instead, since i did not use bleach on the first batch that got the problem, and used bottled water on the process.

When i first encountered this problem it was stronger, and i associated maybe with poor sanitization of the bottles, but then i used bleach on the bottles, rinsed well and then boiled them to clean and then used Peracetic Acid to sanitize.

On the second batch, the bad aftertaste and aroma was a little better, but still persisted.
I thought about wild yeast, and it can maybe be on the Priming Bucket, but i always cleaned it well too, using Alcohol 70% to sanitize.

Anyone had this problem before? It is really probably wild yeast?
If it is, is this process i made (Bleach, rinse very well and use hot boiled water) correct to kill them ?
If it is correct, i will probably extend that to the priming bucket as well.

Best Regards and Thank in Advance

Offline dilluh98

  • Brewmaster
  • *****
  • Posts: 575
Re: Plastic/Phenolic off flavor after bottle carbonation
« Reply #1 on: May 05, 2016, 08:50:47 am »
Did you take apart the spigot/bulkhead/holding screw/PTFE washer on your bottling bucket and clean that too?

I once didn't do such a great job of cleaning my bottling bucket after a session of bottling and two weeks later when I went to use it again, I took everything apart and noticed brown/black gunk in those crevices. I've stopped using bottling buckets partially for this reason.

Offline kramerog

  • Brewmaster General
  • *******
  • Posts: 2262
    • My LinkedIn page
Re: Plastic/Phenolic off flavor after bottle carbonation
« Reply #2 on: May 05, 2016, 09:01:58 am »
It sounds like you have some kind of infection in the brewery.  If every bottle has this problem then the problem isn't with your bottles, but with something that has touched all your beer like fermenter, hoses, bottling bucket, spigots, racking cane, bottling wand, etc.  Scratches in your equipment generally cannot be properly cleaned and sanitized so you may have to retire some of your fermenting or bottling equipment.  You also cannot sanitize equipment that hasn't been properly cleaned except with heat.   You can make bleach solutions for sanitization that do not require rinsing to eliminate rinse water as a source of contamination.   

Offline Guilherme_HCV

  • 1st Kit
  • *
  • Posts: 9
Re: Plastic/Phenolic off flavor after bottle carbonation
« Reply #3 on: May 05, 2016, 09:18:54 am »
Thank you for the answers guys.
Yes, it was on every bottle, so i believe it is an infection.
I am always careful about do not scratch the buckets and with the cleaning of all the parts, but i agree that if it is occurring on all bottles, its is probably not the bottles.
The strange is that the off flavor was not present on the primary fermenter on both batches.

If it is a wild yeast infection, does the bleach approach works or its too risky?

Offline reverseapachemaster

  • Official Poobah of No Life. (I Got Ban Hammered by Drew)
  • *********
  • Posts: 3784
    • Brain Sparging on Brewing
Re: Plastic/Phenolic off flavor after bottle carbonation
« Reply #4 on: May 05, 2016, 09:39:31 am »
What is your water supply? It may be chlorophenol based.

See how the bottles continue to progress. If you see the carbonation increase that is a sign that there is continued fermentation in the bottle and infection is probable. You could get increased off flavors without additional carbonation from an infection but increased carbonation would definitely not be a chlorine problem. It wouldn't hurt to clean and sanitize the equipment anyway but treating for infection if you have a chlorine problem won't cure the problem.

Is there a reason why you use peracetic acid and 70% ethanol rather than the normal sanitizers used in homebrewing?
Heck yeah I blog about homebrewing: Brain Sparging on Brewing

Offline Guilherme_HCV

  • 1st Kit
  • *
  • Posts: 9
Re: Plastic/Phenolic off flavor after bottle carbonation
« Reply #5 on: May 05, 2016, 11:45:15 am »
I use bottled water, and i boil tap water to take off the chlorine water when i will do the peracetic solution

The carbonation seems ok and are very consistent...but i will keep checking.
I am pending more for a wild yeast or infection cause than the chlorine one...even knowing that i was very careful about the cleaning and sanitizing on the priming bucket and bottles.

I am worry about some hard to kill infection...and that is why i used bleach on the second try...and like i said even with a slightly better results the problem persists.

Here in my country we don't have Star San and others sanitizers, so we have Peracetic, Alcohol 70%, Iodophor and Bleach.

Offline ynotbrusum

  • Official Poobah of No Life. (I Got Ban Hammered by Drew)
  • *********
  • Posts: 4888
Re: Plastic/Phenolic off flavor after bottle carbonation
« Reply #6 on: May 05, 2016, 03:20:15 pm »
Tubing is a common culprit, given its propensity to house water drops, even with hanging to dry (mold issues, typically).  The other thought is exposure of the beer to the ambient air while racking to the bottling bucket or to a secondary fermenter - that allows all kinds of microbes to gain access to the beer as a food source.  Keep things covered well in that process to minimize airborne contamination.
Hodge Garage Brewing: "Brew with a glad heart!"

Offline Saccharomyces

  • Senior Brewmaster
  • ******
  • Posts: 1136
  • Deus ex machina
Re: Plastic/Phenolic off flavor after bottle carbonation
« Reply #7 on: May 05, 2016, 05:25:38 pm »
Here in my country we don't have Star San and others sanitizers, so we have Peracetic, Alcohol 70%, Iodophor and Bleach.

That's great because Star San does not kill yeast or mold.  It is an acid-anionic bactericide.  All of the sanitizers that you mentioned are full-spectrum heavyweights.  My bet is chlorine residue.  If you are getting an infection, it is more than likely being pitched with the yeast culture, as most infections are pitched with the culture. I would revisit your yeast handling practices.
« Last Edit: May 05, 2016, 08:31:11 pm by Saccharomyces »

Offline Guilherme_HCV

  • 1st Kit
  • *
  • Posts: 9
Re: Plastic/Phenolic off flavor after bottle carbonation
« Reply #8 on: May 05, 2016, 08:01:52 pm »
ynotbrusum and Saccharomyces thanks for the answers.

About the Chlorine, i do not discard completely but on the first batch i got the problem i didnt even use bleach and I never  used tap water on the production...only bottled water and boiled water in the sanitization solutions, so the possibility for chlorine residue seems unlikely.
Also i did a little research and found on this link http://www.bjcp.org/faults.php the following description, that is not chlorophenol but still is a "Plastic" and seem very accurate for what i am getting :

Plastic Band-aid, electrical tape, styrene  :    Check for infection. Check yeast strain and health. Lower fermentation temperature.

The fermentation temperature was controled as recommended...between 18 and 23 Celsius, but i have to admit that i did not rehydrated the yeast, but used almost a whole 11g package for 10 Liters Batches to avoid underpitching. They were both 1050 - 1060 OG beers and they were Fermentis S-04 on one batch and US-05 on another

About the infection, i just took of the spigots from the buckets and it seems very clean, but anyway i sanitized both buckets (primary and bottling ) spraying alcohol 70% on all the surface andthe  insides of the spigots.
If there is any yeast, mold or bacteria, does this approach with the alcohol works?

Thanks everybody
« Last Edit: May 05, 2016, 08:06:26 pm by Guilherme_HCV »

Offline Saccharomyces

  • Senior Brewmaster
  • ******
  • Posts: 1136
  • Deus ex machina
Re: Plastic/Phenolic off flavor after bottle carbonation
« Reply #9 on: May 05, 2016, 08:37:49 pm »
You should check to see if your municipality uses chloramine.  While I have never personally had to deal with the disinfectant, boiling does not remove chloramine.    Are you boiling your entire wort volume?  Or are you performing a concentrated boil and diluting with water after the boil?
« Last Edit: May 05, 2016, 08:40:32 pm by Saccharomyces »

Offline Guilherme_HCV

  • 1st Kit
  • *
  • Posts: 9
Re: Plastic/Phenolic off flavor after bottle carbonation
« Reply #10 on: May 05, 2016, 09:07:16 pm »
Hi Saccharomyces
Actually i do not use Tap water on the mash, boiling, etc. I use spring bottled water, of the same brand that some of my friends use, with no problem.

I use boil the tap water  only to do the Peracetic Acid solution to sanitize the bottles (some of these same friends dont do that), them dump out the solution after the sanitization.

Offline brewinhard

  • Official Poobah of No Life. (I Got Ban Hammered by Drew)
  • *********
  • Posts: 3272
Re: Plastic/Phenolic off flavor after bottle carbonation
« Reply #11 on: May 06, 2016, 06:49:45 am »
My vote is a wild yeast infection. I have gotten those here and there when packaging off my kegs using a beer gun in the past.  The beer tastes great in the keg, then a couple weeks in a bottle and a plastic note appears.  Happened to my Helles I sent in for NHC this year. Still scored okay, but not as well as it could have without the plastic note. Unlucky bottle.

Offline Guilherme_HCV

  • 1st Kit
  • *
  • Posts: 9
Re: Plastic/Phenolic off flavor after bottle carbonation
« Reply #12 on: May 06, 2016, 12:02:03 pm »
Thanks for the reply brewinhard. I believe that it is the same problem indeed.
Like i said...i do not discard 100% chlorine cause, but it seems unlikely, but i am tending to the wild yeast infection.
Since it seems to affect all bottles and i sanitized like hell them on the second batch...i believe it can be on buckets, or on the inside the spigots.

Do you guys think that the approach i described on the other post with the alcohol 70% may work or i need to do do something more?


Offline Saccharomyces

  • Senior Brewmaster
  • ******
  • Posts: 1136
  • Deus ex machina
Re: Plastic/Phenolic off flavor after bottle carbonation
« Reply #13 on: May 06, 2016, 07:48:53 pm »
I battled a wicked persistent wild yeast problem for almost a year after I switched to Star San from using bleach/vinegar and iodophor as sanitizers, which is how I discovered that Star San is not an effective yeast and mold killer.  A serious bleach "shock" followed by switching back to using bleach/vinegar and iodophor as my sanitizers eliminated the problem for good.

I do not see how you are getting a wild yeast infection late in the game using peracetic acid.  That stuff goes completely cro-magnon on microflora.   At 110ppm (many breweries use 200ppm), peracetic acid completely eradicates even the toughest to kill microflora in under 3 minutes at 20C/68F; therefore, unless you are doing the drive-by sanitation method of spray-and-go that seems to be popular these days coupled with less than adequate cleaning, nothing should be alive in your fermentation vessels, bottles, or racking equipment. 

It would help if detailed your process from start to finish, including how you clean and sanitize your gear.  Additionally, I need to know if you sanitize your scissors and the outside of the dry yeast packet before you pitch.  As I mentioned earlier, most infections are pitched with the culture.  The invaders are kept at bay while the culture is active and come to life after it has entered quiescence.

« Last Edit: May 07, 2016, 04:52:48 am by Saccharomyces »

Offline Guilherme_HCV

  • 1st Kit
  • *
  • Posts: 9
Re: Plastic/Phenolic off flavor after bottle carbonation
« Reply #14 on: May 07, 2016, 04:30:52 pm »
Hi guys,

I will describe with more details my process, and the small differences between the two that presented the problems.

First i washed all the aluminium that would be used on the Mash and the Boiling, and them I sanitized them with the alcohol 70%, them I put all the grain and kept the mash at about 68 C for 60 to 70 minutos, did the Vorlauf and after that I did the sparge and transferred  the wort to the boiling tun.
Always using spring bottled water.

After the boiling i sanitized the fermenter bucket with the alcohol 70%, including the spigot but i have to admit that I didnt took it of, just sprayed the alcohol, and then transferred the wort to the fermenter after chilling it out.

Took the 11g package of Fermentis Dry Yeast and pitched on the wort. When in opened the package i had my hands sanitized with alcohol 70% but didnt sprayed it outside the package.

After that the fermentation went ok, with the attenuation a little bit smaller than expected, and after 7 days i maturated the beers for 2 weeks. I proved the beer after these 3 weeks and it apparently didnt showed any off flavors.

I sanitized the bottles with Peracetic Acid solution and  did the sanitization of the priming/bottling bucket with the alcohol 70% just like the fermenter and transferred the beer to it, then i did the priming and bottled it.
The off flavor appeared apparently only after the secondary fermentation on the bottle.

The only difference between the batches, is that on the second one, i sanitized the bottles like hell, with bleach/water solution boiled it and then used the peracetic acid.

I believe that was the process.

Best Regards and Thank everybody for the help until now